An overturned tractor-trailer let loose millions of honeybees on Sunday and left a sticky mess on a major highway south of Atlanta, after hitting a guardrail and spilling its cargo of hives and honey.

“It looked like there was a rain cloud around everybody,” Monroe County Emergency Management Agency director Matthew Perry said on Monday. “There was a giant mound of honeycomb and bees.”

A portion of Interstate 75 was closed briefly, and clean-up of the honey and swarming bees took 15 hours, Perry said.

Authorities sought help from beekeepers, who arrived with protective gear to assist with the potentially dangerous swarm.

The debris was pushed to the median with a small bulldozer and then beekeepers began piecing the broken hives back together so the bees would return, Perry said. The hives were loaded back into bee boxes and hauled away.

No one was stung or injured, in part because the weather was cool and the bees docile, Perry said.

“When you have an interstate like I-75, you never know what’s going to come passing through,” he said.